Conventionally, HFC refrigerants that have high global warming potential (GWP) have been known as refrigerant applicable to a refrigeration cycle of an air-conditioning apparatus and the like. For example, HFC-R410A which is a near azeotropic refrigerant, and HFC-R32 which is a single refrigerant are mainly employed. In addition, in recent years a refrigeration cycle apparatus has been proposed that employs a non-azeotropic refrigerant mixture containing a HFO refrigerant having low GWP such as HFO-1234yf or HFO-1234ze, and an R32 refrigerant (see, for example, Patent Literature 1).